The demand for energy sources other than fossil fuels has led to extensive development of devices for utilization of solar energy. Among such solar energy devices have been various collector panels heating liquid carried in tubing, reflector panels, lenses and other radiant energy concentrators and devices for transforming solar radiation directly into electrical energy. Numerous problems have been encountered in the design of efficient solar energy collection apparatus. Some problems related to the positioning of the collection apparatus for maximum energy absorption. Because the angle of incidence of the sun varied during the day, solar energy collection devices had to be repositioned for efficacious operation.
With regard to positioning mechanisms, solar energy applications not only mandated a high degree of accuracy but also high rigidity so that collection panels could not move as a resuit of their own weight or wind loads. To obtain accurate angular positioning, high gear ratios were necessary, yet inertial mass was required to be minimized. Further, stability in the presence of extreme temperature and humidity environmental factors was required.